Accurate Testing Starts with the Preload

Often when visiting customer sites, our service engineers find machines that have basic setup problems that can have a large effect on the accuracy of test results. A very common problem is testing with poorly preloaded grip locknuts. Placing a specimen under tension also places all items in the load string – grips, grip adapters, load cell, and so on – under tension as well.


Grips Supplied with Locknuts
If the locknut is insufficiently tight, the forces experienced during a test, particularly a cyclic test, can cause backlash in the load string leading to errors in the test data. Before testing, make sure that you preload the load string, using a load greater than the expected maximum load, and tighten the grip locknuts while the load is applied. Read more

Full Fluid Jacket – Liquid Body Armor

Humans have waged war on one another for centuries. Weapons have evolved from sticks and stones through cutting and bludgeoning implements to today’s smart bombs and missiles. But the evolution of the means to protect oneself from the impact of those weapons has not kept pace. However, a new technology combining two advanced materials – Kevlar and shear-thickening fluid – may hold the promise of light, flexible and effective full body armor.

Today’s body armor is a compromise between protection and agility. Most modern body armor comprises many layers of woven Kevlar, sometimes with ceramic plates to give extra protection. Kevlar is an aramidic fiber, which forms hydrogen bonds between its chains of molecules and thus has a very high tensile strength and high toughness. It is five times stronger than steel on an equal weight basis and it already saves countless lives.

Although Kevlar offers vastly increased protection for the wearer, it does have some drawbacks. For effective protection, up to 30 or 40 layers of Kevlar are needed. This many layers, together with additional ceramic plates, make the armor bulky, stiff and heavy, meaning that the wearer cannot move around as easily. Also, body armor does not offer protection for extremities, such as arms, legs or the neck because the number of layers of Kevlar needed to offer sufficient protection would be too stiff and bulky for use as sleeves, trousers, and so on.

A great deal of largely US-military-funded research has taken place over the last few years into combining Kevlar fabric with a shear-thickening fluid. Shear-thickening fluid is an example of a "smart material," a class of materials that can sense and respond to changes in the environment, for example through the application of electricity or magnetism, or to changes in temperature. Shear-thickening fluids increase their viscosity in response to changes in pressure. An example of a fluid under research is ethylene glycol containing suspended nano-particles of silica. Under normal conditions, the particles are weakly bonded to each other and can move around with ease. The shock of an impact strengthens those chemical bonds and the particles lock into place. Once the force from the impact dissipates, the bonds weaken again.

The liquid technology can improve both the performance and the utility of Kevlar fabric. Saturating Kevlar fabric in a shear-thickening fluid causes the fluid molecules that are already bonded with each other to also form weak chemical bonds with the polymer chains of the Kevlar fibers. The weak bonding allows the fabric to remain flexible. When a projectile strikes the fabric, it becomes rigid within two-thousandths of a second, preventing penetration. Furthermore, the reduced flow of the fluids in the liquid armor restricts the motion of the fabric yarns in relation to each other, resulting in an increase in the area over which the impact energy is dispersed. As a result, the material does not distort as much as the standard body armor, which generally extends inwards substantially when a projectile strikes, causing considerable pain and injury. Once the event is over, the fabric returns to its former flexible state.

The mechanical properties of the material are being evaluated using a wide range of tests and test equipment. Drop towers test puncture resistance with knives and icepicks as well as various shapes and sizes of instrumented tups. Load frames are used to test resistance to abrasion, fiber pullout, and tearing. Gas guns are used to fire ballistics such as bullets and shrapnel.

Impregnating Kevlar with a shear-thickening fluid strengthens the fabric to such an extent that improved protection can be achieved with a material that is one-third the thickness of Kevlar alone. Therefore, the body armor can be lighter, more flexible and yet offer greater protection from projectiles, shrapnel and explosive devices – the major causes of injury and death in modern conflicts. Seventy per cent of all non-fatal injuries and sixteen per cent of deaths in a war zone are due to trauma to extremities. Because fewer layers are necessary with the new material, supple armor for arms and legs is now possible. Extremity armor using shear-thickening fluid impregnated Kevlar could significantly reduce the number of injuries in battle as well as saving lives.
Read more

The Burj Khalifa – Cast in Concrete

The Burj Khalifa, the world’s tallest building, has a laundry list of superlatives. Greatest number of stories, highest occupied floor, longest travel distance elevator, world’s highest swimming pool. Perhaps none of these would have been achievable without the great advances that have been made in concrete technology over the past 20 to 30 years.

Until the 1990s, concrete wasn’t a cost-effective solution for the construction of tall buildings – it had limited strength, it was heavy, and fabrication was longer than for steel construction. Generally steel was looked at as the solution for super-tall buildings.
However, there have been significant advances in many aspects of concrete technology with great increases in strength, modulus and durability. High-performance concrete (HPC) mixtures provide a wide range of mechanical and durability properties to meet the design requirements of a structure. Even so, the challenges facing the structural and construction engineers on the Burj Khalifa project have been huge. Most of the Burj Khalifa is a reinforced concrete structure, except for the top, which consists of a structural steel spire with a diagonally braced lateral system. 330,000 m3 (431,600 yd3) of high-performance concrete is used throughout the building.

One of the major requirements for the successful completion of this project was the ability to pump the concrete slurry up to a height of 600 meters (1968 feet) in a short enough time span (around 30 minutes) to ensure the concrete remained workable and retained its high performance properties. Three high-pressure pumps were used at the construction site to lift concrete up to crews working at unprecedented heights.

To decrease construction time, the concrete was designed to be self-consolidating (SCC), meaning a concrete mix that leveled itself solely due to its own weight, with little or no vibration. It spread into place, filled formwork, and packed tightly into even the most congested reinforcement, all without any mechanical vibration.

Great care was necessary to achieve and maintain the desired performance of concrete in this region. The Middle East is not a benign environment for concrete due to the extremely wide range of temperatures experienced throughout the year. The ability to pump and place concrete at high ambient temperature to significant heights while preventing excessive cracking and possible service life issues in the strong drying conditions was vital for the efficient and economic use of HPC. During the summer months, when shade temperatures can exceed 50°C (122°F), the concrete’s water content was almost completely composed of flake ice to achieve the common limit of 32°C (90°F). Whenever possible, and in particular during the hottest months, all pumping of concrete took place at night.

The importance of extensive testing of the concrete could not be overstated. Prior to the construction of the tower, extensive concrete testing and quality control programs were put in place to ensure that all concrete works were done in agreement with all parties involved. These programs started from the early development of the concrete mix design until the completion of all test and verification programs. Five different concrete mixture designs were tested. The testing regimes included, but were not limited to the following:

• Test the mechanical properties of each mixture, including compressive strength, modulus of elasticity, and split tensile strength
• Test and measure the concrete properties (fresh and hardened) before and after pumping
• Test for creep and shrinkage for all mixtures
• Test for water penetration and rapid chloride permeability
• Test the shrinkage of the concrete mixtures
• Pump simulation testing for all concrete mixtures grades up to at least 600 meters (1968 feet)

The Burj Khalifa is the current state-of-the-art in super-tall buildings, exploiting the latest advances in construction materials and methods. The result is a structure that surpasses anything that has been achieved before. Read more

Seeking Your Input .....

We've been blogging and you've been reading, but are you finding what you've expected at the Instron Community?

We're interested in hearing your input on articles to focus on for 2012 - more technical tips, more industry news ..... What do you find beneficial? I've included a poll on the right side of our blog - please take a few moments to fill it out or include your comments below.

Thanks so much and happy holidays! Read more

Liquidmetal – Not Just for Terminators

Materials scientists have been trying for years to discover and develop a product that could be molded into complex shapes with the ease and low expense of plastic while retaining the strength and durability of metal. Recently, a team led by Dr. Jan Schroers, a materials scientist at Yale University and the former Director of Research at Liquidmetal Technologies, has recently developed some metal alloys that can be blow molded like plastics into complex shapes that can't be achieved using regular metal, without sacrificing the strength or durability that metal affords.

Dr. Jan Shroers with metal bottle
Photo courtesy of Dr. Shroers

Liquidmetal is a commercial name for a series of bulk metallic glass (BMG) alloys developed by a CalTech research team and marketed by a firm called Liquidmetal® Technologies. BMG alloys are solid at room temperature, but they become increasingly soft and liquescent at higher temperatures rather than exhibiting a fixed melting point as with a conventional metal.

It’s the atomic structure of a BMG alloy that differentiates it from a conventional metal. The atomic structure of a conventional metal is crystalline, with repeating crystal patterns in planes, and usually containing dislocations, or irregularities, in the structure. The tendency of the crystalline structure to slip and deform under load limits the overall mechanical performance of conventional metals.

The atomic structure of BMG alloys is amorphous, where no discernible patterns exist in the atomic structure. The absence of grain boundaries and dislocations results in a material with a large elastic strain limit and a very high yield strength, close to the theoretical limit. As an example, one zirconium-based BMG alloy exhibits a yield strength of up to 2 GPa and an elastic strain limit of about 2%. BMG alloys also demonstrate excellent corrosion resistance, very high hardness, and excellent anti-wearing characteristics, while also being able to be heat-formed in processes similar to those used with thermoplastics.

Liquidmetal was introduced commercially in 2003 and has been used to manufacture electronic casings, medical devices, jewelry materials, and sporting goods. Die-casting is the main manufacturing process, but it is subject to conflicting demands. The conditions needed to obtain high-quality casts are slow cooling and small temperature gradients. In a die-cast process, the liquid BMG must fill the entire mold cavity while at the same time be cooled fast enough to avoid crystallization. This makes casting of parts with complex geometries difficult.
Schroers claims that the alloys can be blow molded just as cheaply and as easily as plastic. So far his team has created several complex shapes, such as metallic bottles, watch cases, miniature resonators, and biomedical implants that are seamless, twice as strong as steel, and can be molded in less than a minute.

On the tech blog Cult of Mac, Schroers said it is likely Apple, who has been interested in the possibilities afforded by BMGs for some time, will invest heavily in commercializing the technology. Apple has a long history of pioneering cutting-edge manufacturing techniques, and its long-standing interest in design makes it likely to explore the material’s capabilities.
Sources
“Amorphous Metal Alloys Form Like Plastics”, Advanced Materials & Processes, January 2006, Jan Schroers and Neil Paton
“Thermoplastic blow molding of metals”, Materials Today, Jan-Feb 2011, Volume 14, Number 1-2, Jan Schroers, Thomas M. Hodge, Golden Kumar, Hari Raman, Anthony J. Barne, Quoc Pham, and Theodore A. Waniuk.Yale University.
“Stronger than steel, novel metals are as moldable as plastic.” ScienceDaily, 8 Feb, 2011. Web.
“The Superplastic Forming of Bulk Metallic Glasses”, Journal of Metals, 2005, 57, 35-39, Jan Schroers Read more

When Did You Last Change Your Oil?

It’s no secret that hydraulic fluid contamination leads to increased wear and corrosion, and decreased fluid life and system performance. At the same time, you want to maximize the life of your oil to reduce costs and downtime. It’s a balancing act.

Here are some tips for getting the most out of your hydraulic fluid:

• Don’t skimp on quality. Use a good quality hydraulic fluid from a reputable manufacturer following the specification recommendations from the pump and system manufacturer.
• Keep hydraulic fluid clean, cool, and dry. Maintain filtration and use clean lines to transfer hydraulic fluids into your equipment.
• Proactively analyze both your used fluid and your in-service fluid for contamination, oxidation, and to assess wear on the system.

Increasing the frequency of fluid changes may prove to be particularly cost effective in the long term. Research by the British Hydromechanics Research Association (BHRA) and National Engineering Laboratory indicated potential life extension factors of 10 - 50 times were possible on a variety of hydraulic equipment depending on oil contamination level. Read more

Q. Our testing lab is moving to a new building. Do our testing systems require recalibration after the move?

We strongly recommended that you recalibrate your systems after a move. In fact, many ASTM and ISO testing standards such as ASTM E4 and ISO 7500-1, have a mandatory requirement for recalibration.

If you have questions about this or you would like assistance with moving and recalibration of your system, please contact your local Instron service office. Additionally, we recommend taking into account other appropriate services at this time including preventive maintenance, system set up, and training. If you would like assistance with moving and recalibration of your system or if you have questions, please contact your local Instron service office. Read more

Syringe Testing is Painless!

Nobody really likes getting shots; however they have become less inconvenient for patients throughout the years thanks to the constant improvement of the design and materials used by syringe manufacturers.

Plastic disposable syringes were first introduced in 1961. The “disposable revolution” brought considerable benefits, the main one was the drastic reduction of infections transferred between patients since a syringe was only used once. In addition, the new disposable syringes optimized medical operations because the sterilization process for reusable glass syringes was no longer required.

One key factor in the shot process is how much force is required to operate the plunger of the syringe in both directions. This force level must allow the doctor or nurse to easily operate the syringe without causing harm to the patient.

Watch a video of a test (which meets ISO 7886-1 Annex G) that measures the required forces to operate the plunger of a disposable syringe.

Read more

Building Bridges at SAMPE

With more than 250 people in attendance and anticipation, we hosted the 3rd Annual Bridge Contest at the 20th SAMPE France Technical Meeting. This year we had 10 teams from 8 universities trying their hand at building a bridge strong enough to beat the other nine teams ....

We saw carbon fiber bridges constructed of special shapes (a fish belly), square bridges, and a very thin and flexible bridge which never broke. All teams did a great job constructing their bridges - it was impressive!

The winning bridge, designed with an arche shape, was from University Paul Sabatier, Toulouse with a strength of nearly 30 kN.

Next year, we'll need to supply a floor machine for the contest.

In addition to all those who participated in the contest, we like to give a special thanks to Mr Kauffmann and Magnin from SAMPE France.

Other pictures will be available soon on the Sampe France website - be sure to check them out! Read more

The Versatility of Milk Crates

About 24 months ago my car was vandalized and left resting on two milk crates ... why was it "resting" on the crates? Because my alloy wheels where missing. As much as I was shocked that someone would steal my wheels, I was more amazed that milk crates had the strength to hold up my Honda Civic ... and it got me thinking, "how much force can a milk crate take before failing?"

So we put the crates to the test - watch the video!

Read more

Instron Named Supplier of the Year

To find our place in the UK Plastics Testing Industry, we attended Interplas, where we met many customers and potential customers. This allowed our Application Experts the opportunity to understand and learn more about the market. During Interplas, we were entered into the European Plastics Product Manufacturer (EPPM) Supplier of the Year Awards; a contest where an independent research company contacted readers of EPPM and ask who is their preferred supplier. Based on 11 different categories, as well as overall brand image in 2011, Instron came out on top, winning Testing & Inspection Machinery Supplier of the Year.

It's not every day a Materials Testing Manufacturer is voted "Supplier of the Year" ..... so, we'd like to take this time to thank the readers of EPPM and everyone who made this a reality for Instron! Read more

Free Webinar: Modernizing Your Old Tester

Are you in need of a new testing system, but just don't have the budget right now for new equipment? Did you know you can modernize your test frame at a fraction of the cost of a new testing system? Join our free webinar (Tuesday, December 6th at 11 AM EST) and participate in the discussion with Frank Lio on the different types of retrofits, the retrofit process, technical and user benefits, costs, and whether your frame is a good candidate.

Register for the webinar - or leave us a message below! Read more

From Bike Riding to Subcontracting ...

Jönköping, Sweden is home to the largest recreation bicycle ride in the world. For those that are interested by a 300 km pedal around one of the largest lakes in Sweden, you’ll have to wait until June – VÄTTERNRUNDAN.

The city also hosts the largest subcontractor tradeshow and the 28^th Elmia Subcontractor proved to be another interesting event. With more than 1,200 companies exhibiting it is always an important meeting place for the Swedish industrial community. As the name suggests, the focus is on the subcontractor industry, a lot of whom are Instron customers. We, therefore, found ourselves spending as much time with other exhibitors as we did with the visitors to the fair.

This tradeshow was in stark contrast to the usual application specific events we attend and the diversity of product on display was overwhelming. We had discussions on testing: hearing aids, engine mounts, lifting devices, composite prostheses, and the buckling of felt paper! As some of our British colleagues attended this show, they found time to debate tactics for the upcoming England vs Sweden soccer match next week. Check out the video! Read more

Project 2.6g 329m/s

It's been fascinating to look back over some of the previous articles covering the development and testing of new materials and new applications for materials. Some of the most popular articles judging from your feedback have been those that have looked at the ongoing efforts to develop synthetic spider silk and the efforts to manufacture effective lightweight body armor. Recently, an amalgamation between art and science has resulted in the development of what many newspapers and popular science publications have trumpeted as bulletproof human skin.


Bulletproof skin. The words conjure up images of bullets bouncing off the superhero’s chest as the villain opens his eyes wide in amazement. The recent flurry of hyperbolic headlines in newspapers, the web, and popular science magazines announcing the arrival of bulletproof human skin made it seem as if that possibility was already here. “Scientists to Engineer a Human with Bulletproof Skin” proclaimed the International Business Times on August 23, 2011. The reality is rather more mundane although it still offers exciting possibilities. The Designers & Artists 4 Genomics Award, DA4GA, a competition launched by the Waag Society in Amsterdam, Holland, invited emerging artists and designers to submit projects exploring biotechnology. One of the winning projects, named 2.6g 329m/s, is a manufactured human skin that has properties that make it very strong and resistant to penetration. The name comes from the performance standard for Type 1 bulletproof vests. 2.6g 329m/s is the maximum weight and velocity of a traveling bullet from which a Type 1 bulletproof vest should protect you.

The project artist, Jalila Essaidi, worked with the Forensic Genomics Consortium Netherlands to develop human skin with a layer of transgenic spider-silk sandwiched between the epidermal and dermal layers. The silk is a product of research done by Utah State University researcher Dr. Randy Lewis. It is produced from goats and silkworms that have been genetically modified to produce the two proteins necessary to make spider silk. The silk is harvested from the animals and woven, using special bulletproof vest techniques, into a scaffold upon which is cultured human skin cells.

The team manufactured skin samples using two types of silk: one from unmodified silkworms and one from the transgenic silk. Essaidi mounted the skins on gelatin blocks and, using a high-speed camera, filmed bullets fired at the skins. A bullet fired at a reduced speed pierced the skin woven with an ordinary worm's silk. When tested with skin manufactured from Lewis' genetically engineered silk, the skin didn't break. However, neither skin was able to repel a bullet fired at normal speed from a .22 caliber rifle. Furthermore, the bullet that did not penetrate the skin still traveled 5 cm into the gelatin block.

Lewis was happy to collaborate in the project, viewing it as a way to widely demonstrate the properties and capabilities of the transgenic silk. However, he downplays the potential bulletproof applications of his research. In a recent interview on CNN, he said that this was an interesting experiment but he didn’t see it as the future for mankind. His interest lies more in the possibility that growing human skin cells on the silk may eventually enable doctors to use the material to replace large amounts of human skin and cover large wounds or treat people with severe burns. The material's strength and elasticity would enable doctors to cover large areas without worrying about it ripping out — a big advantage over small skin grafts. He says it may be possible to use the genetically engineered silk as a framework for growing ligaments or tendons with better mechanical properties than those provided by nature.

So while the long sought-after “warrior gene” may still live in the domain of comic books, the ongoing research into biosynthetic material engineering comes closer to offering major medical benefits to the human race. Read more

Keep It Consistent

Consistency is the key to accurate and repeatable test results. Variations in the test setup, test procedure, environmental conditions, and operator input can all affect the test results.

• Make sure that the appropriate gauge length, test speed, type and capacity of load cell, and grip and grip jaw selection are appropriate.

• Insert the specimen in the grips correctly and clamp it securely. Manual wedge grips are difficult to tighten consistently even with the same operator. You can minimize this variation by using pneumatic grips that always grip at the same pressure.

• Control the temperature and humidity to standard laboratory conditions or record the actual conditions when a test is performed.

• Ensure that your testing system and accessories are regularly serviced and calibrated to keep them at the peak of efficiency. Read more

Question from a Customer

Q. What is a durometer? Is it an instrument or a measurement?

A. It’s both. A durometer is an instrument used to measure hardness and is typically used on polymeric, elastomeric, and rubber materials. Durometer also refers to the hardness result obtained.

There are several scales of durometer, used for materials with different properties. The most common scales are the ASTM D2240 type A and type D scales. The A scale is for softer materials, while the D scale is for harder ones. However, the ASTM D2240-00 testing standard details 12 scales, depending on the material to be tested; types A, B, C, D, DO, E, M, O, OO, OOO, OOO-S, and R. Each scale results in a value between 0 and 100, with higher values indicating a harder material.

Durometer is a dimensionless quantity that offers a comparative value within any particular scale. There is no simple relationship between a material's durometer in one scale, and its durometer in any other scale. Read more

What is Potting the Bone?

During a conversation with one of our Application Engineers, he brought to my attention that many of our customers ask him how to "Pot" the ends of "bones" and perform compression, tensile, or fatigue test on the bone .... So, we're sharing his techniques with you.

Technique #1

• “Paint” the end of the bone with Krazy Glue or equivalent and let it dry.
• Use 3M ScotchWeld Acrylic Adhesive; this is a two part epoxy so you will need to use a mixing nozzle to get the correct blend.
• Put the epoxy into a “sawed off” hollow square tube (you can purchase long lengths of square metal tubing from many local steel suppliers).
• Put duct tape on one side of the tube to prevent epoxy from escaping.
• Place one end of the chicken bone into the epoxy and let cure (room temperature, 8 hours or so).
• Do the same to the other end of the chicken leg (room temperature, 8 hours or so).

You will now have an “assembly” that can be put into the test machine and tested.

Technique #2

• Same as above, but no need to “paint the ends with Krazy Glue”.
• Use Cerrobend Alloy; this melts at 158° F and has a very fast cure (about 10-15 minutes maximum).
• Here is one possible supplier. There are many more…
• Pour it into the square tubing as described above.

Read more

New Training & Research Center in Moscow

Ben Randles, Instron’s North Europe Sales Engineer, and Dmitry V. Livanov, Rector of the National University of Science and Technology "MISiS", signed a partnership agreement and officially opened the new International Scientific and Research Centre in Moscow.


The aim of the new centre and the joint collaboration, which will also be supported and assisted by Instron’s long-term Russian partner “Novatest LLC”, is to provide:

• The highest standard of training for students, using the latest Instron equipment and software
• Extended vocational training courses for teachers & professors in modern methods of mechanical testing and experimentation
• High-end research capability for MISiS specialists
• R&D Contract testing business from Industrial customers for MISiS
• A reference site and training facility for Instron

Read more

Using Video Capture to Develop Global Quality Control

Have you ever run a test and wanted to know what the product or material looked like or what the force/displacement is at a certain moment in time during the test? Our friends at Vartest Laboratories in New York City use the Video Capture Module for Bluehill® to investigate failure modes of individual specimens. The Video Capture Module allows users to view the test curve and a recorded video of the test at once.

You can read their full blog post on their experience and findings. Read more

Shanghai Composites Seminar

On October 26, 2011, Instron hosted a seminar on Composites at the Shanghai City Hotel in Shanghai, China. Approximately 35 guests from industry and academia attended the seminar, which featured talks on “Trends in Composites Testing”, “Typical Applications and New Grips and Fixtures” and “Bluehill Software Features for Composites Applications” by Ian McEnteggart.

Mr. Shen Wenrong, from Instron China's Engineered Solutions Group, presented “Strain Testing Solutions for Composites”, covering contacting and non-contacting extensometry.

Dr Zhou Zhulin, a special guest from the Shanghai Fiberglass Institute, also delivered a speech in the seminar.

This represents one of the many ways that Instron is reaching out to the composites industry - making sure that we stay abreast of the latest technologies and innovations for testing and more!

Would you be interested in attending a composites seminar hosted by Instron? Or how about a composites webinar? Let us know. Read more

Happy Halloween from the Great Pumpkin

As the last in our 3-part series of squashing fall vegetation, we bring you .... the great pumpkin video. Although the largest of the pumpkins and dumpling squash, this pumpkin broke at the lowest force - 450 lbf. And according to our Application Lab, it was "perfect".

We wish you all a happy and safe Halloween. Read more

Trends and the Future - Composites

Will you be in the Boston area on Thursday, October 27th? Are you interested in emerging applications for glass and carbon composites, the increasing attention paid to recycling, or challenges that are associated with mechanical testing of these materials? If so, stop by the Hyatt Regency Cambridge for the ASM's October meeting that will focus on a discussion with Lorenzo Majno about the developing markets and challenges for composite materials. Find out more information on the meeting ....

The meeting starts 6:00 PM with a social time, dinner is served at 6:30, and Lorenzo's discussion begins around 7:30. If you can't make the entire evening, at least stop in to chat with Lorenzo. The fees and other information is directly below.

Meeting Cost
ASM Members: $28
Non-Members: $35
ASM Student Members: $15
Non-Member Student: $18
ASM Job-Seeker: $15
New Chapter Member - First Meeting: $0
Lecture Only: $0

Reservation Details
To make dinner reservations, please call 1-800-467-1057. When prompted, record your name, phone number, size of your party and a choice of dinner (chicken, fish, or vegetarian). Read more

Graphene – The Miracle Material?

Graphene, a two-dimensional solid comprising a one-atom thick sheet of carbon, has recently overtaken carbon nanotubes as the research material of the moment. Graphene was first isolated in 2004 by scientists at the University of Manchester in England, but the focus for some years has been on developing ways to manufacture graphene sheets of sufficient size and quality to enable effective research into its properties. These efforts have paid off and recent research studies have established graphene as the strongest material in existence. It also has very high thermal and electrical conductivity. These properties are stimulating the imaginations of researchers worldwide and may lead to the development of new generations of mobile electronics, computers, and even nano-sensors used for oil exploration.

Graphene has long been known to exist. Graphite, such as that used in pencil leads, consists of layers of graphene; carbon sheets stacked together like a deck of cards. The molecular forces holding each card to its neighbors are weak, but researchers had not developed the techniques needed to slide a single card out of a graphite deck.

In September 2004, researchers led by Professor Andre Geim, a physics professor at the University of Manchester in England, isolated layers of graphene with a technique that is now scientific folklore. They placed a graphite flake on a piece of adhesive Scotch tape, folding the tape over and pulling it apart, cleaving the flake in two. Folding and unfolding repeatedly caused the graphite to become thinner and thinner. Then they stuck the tape to a silicon wafer and rubbed it. Some graphite flakes stuck to the wafer, and some of those flakes were one atom thick. It has become known as the “Scotch tape” method of graphene production.

Graphene is now typically created using a chemical vapor deposition process, in which carbon-containing gases are made to decompose on a copper foil substrate. Until recently, the process was plagued by problems of poor crystal consistency, but a new production method utilizing hydrogen gas is reportedly capable of producing graphene sheets with perfectly hexagonal, single-crystal grains. The researchers claim it could lead to the large-scale production of higher-quality graphene.

Graphene’s carbon atoms are arranged in a hexagonal lattice and, although the substance is chemically very simple, it has astonishing properties. Graphene is light, flexible, and stronger than steel. It conducts heat 10 times faster than copper and can carry 1,000 times the density of electrical current of copper wire. Graphene is proving to be a revolutionary material that could change the technology of semi conductors, LCD touch screens and monitors; create super-small transistors and super-dense data storage; increase energy storage and solar cell efficiency; and transform many other applications.

Researchers at Columbia University, New York, have evaluated the strength of graphene using the diamond tip of an atomic force microscope to apply loads and measure its deformation and rupture strength. They estimate that graphene has a breaking strength of 55 newtons per meter. Scaling that up into everyday terms, it would require a force of 2000 kg to puncture a sheet of graphene that is as thick as ordinary plastic food wrap making graphene the strongest material measured.

University of Maryland researchers have shown that electrons travel over 100 times faster in graphene than in silicon. Their results, published online in the journal Nature Nanotechnology, indicate that graphene holds great promise for replacing conventional semiconductor materials such as silicon in applications ranging from high-speed computer chips to biochemical sensors.

Graphene also possesses superior optical and thermal properties that could make it less expensive and use less energy inside portable electronics like smartphones. The University of California recently has created a miniature optical device that could enable the large data files for 3D movies to be downloaded to a smartphone in seconds.

Research institutes, universities, and companies around the world are investigating ways to build devices such as touchscreens, ultrafast transistors, and photo detectors using graphene. In April, IBM demonstrated a graphene transistor that can perform 155 billion cycles per second, which is about 50% faster than previous experimental transistors shown by the company's researchers.

One of the most exciting recent discoveries related to graphene is that water flowing over the surface of a graphene sheet will generate electricity. Led by Professor Nikhil Koratkar of the Rensselaer School of Engineering, researchers investigated how the flow of water over surfaces coated with graphene could generate small amounts of electricity. The research team demonstrated the creation of 85 nanowatts of power from a sheet of graphene measuring .03 millimeters by .015 millimeters. This amount of energy should be sufficient to power tiny sensors that are introduced into water or other fluids. One of the areas where this property could be highly advantageous is oil exploration.

Hydrocarbon exploration is an expensive process that involves drilling deep down in the earth to detect the presence of oil or natural gas. Oil and gas companies envisage enhancing this process by sending out large numbers of nanoscale sensors into drilled wells. These sensors, carried by pressurized water pumped into the wells, would travel horizontally through the network of cracks and fissures that exist underneath the earth's surface.

It’s not possible to power these micro-sensors with conventional batteries, as the sensors are just too small. However, a coating of graphene around the sensor may capture enough energy from the movement of water over the sensors to provide a reliable source of power for the sensors to transmit collected data and information back to the surface. Oil companies would no longer be limited to vertical exploration, and the data collected from the sensors would arm these firms with more information for deciding the best locations to drill.

About 200 companies and start-ups are now involved in research around graphene. In 2010, it was the subject of about 3,000 research papers. However, amidst all this excitement, many scientists, including Dr. Geim who, with Dr. Konstantin Novoselov, won the Nobel Prize for physics in 2010 based on their graphene work, recommend caution. Some are certain that graphene will not do everything that has been thought up for the material because the properties have only ever been demonstrated on a very small scale. Graphene seems to have great potential, but there are few examples so far of it working in our macro world. Read more

Are You Using Event Log Files?

Many WaveMatrix™ customers are unaware of the existence of an event log file that is created each time you run a test. The log file, named [testname].log, details each separate event that occurs from the moment the test starts and contains useful information such as how many cycles have run, test values, and more. It is a great resource for troubleshooting problems such as why the test stopped unexpectedly. The file is stored alongside the other results for that test.


Here is a typical line from a log file showing the test stopping when the position limit is exceeded:

Read more

A Question from a Customer

Q. Some Bluehill^® calculations don’t show a result when I think they should. Where can I find information on the calculations?

A. Bluehill contains a comprehensive online document - Calculations Library - that has details of every calculation in the Bluehill suite.

It details the calculation algorithm, any calculation dependencies (some calculations cannot work until other results are calculated), and the reasons that a calculation may fail to work. You can open the Calculation Library document using the Help menu in Bluehill.

All of the online calculation information is also available on your software media as a PDF file entitled Calculation Reference. Read more

Did You Experience the First Annual Medtec India?

Did you know that 40% of the world’s population lives in China and India? With increasing global competiveness, expanding healthcare coverage, and increasing wealth, both of these countries are poised for substantial increases in the utilization of medical devices.


To that effect, the Nehru Center in downtown Mumbai just hosted the first Annual Medtec India conference and exhibition. More than 30 vendors entertained 500+ visitors interested in seeing what is the latest and greatest in terms of processing equipment, testing equipment and a multitude of technical services. Additionally, speakers from multi-national companies like Stryker, Johnson & Johnson and Abbott Vascular discussed the state of the regulatory environment in India; addressing challenges, limitations, and opportunities.

The Instron Bio Team manned a booth which highlighted our capabilities in medical device testing. We brought an E1000 with Wavematrix™ Software to demonstrate our ability to address the ongoing need for increases in fatigue testing within this application space. Excited about our ongoing business expansion in India, we are looking forward next year’s expanded conference (4 times as many exhibitors anticipated) in New Delhi.

If you have any questions about the evolving market or any interesting stories about working in India, let us know! Read more

What's the Connection to Hardness Testing?

Stop by the Wilson Hardness blog - Hardness Testing Connection - and find out! Hosted by the Wilson Hardness Group, this valuable resource is ideal for getting the most up-to-date information and relevant news in the world of hardness testing. We encourage you to visit the blog and connect with the Hardness team by submitting comments, asking questions, and sharing your thoughts Read more

From Dumpling Squash to Dumpling Pancake

The next video in our three-part series of squishing our favorite fall vegetables includes the dumpling squash. Although this vegetable could not compare to the messy little pumpkin, it did hold up to 780 lbf before compressing into a nice squash pancake. Now, all we need is a good dumpling squash recipe.

Read more

How Much Pressure can You Withstand?

Did you know that when O-rings - solid-rubber seals shaped like a doughnut - are compressed between mating surfaces they block the passage of liquids or gases? O-rings are one of the most common seals used in machine design because they are inexpensive, easy to make, reliable, and have simple mounting requirements. They can seal tens of megapascals (thousands of psi) pressure. To put this in perspective as to how much pressure they can seal, the air pressure in one tire of a family sedan is 32 psi.

O-rings are used broadly in many industries including petrochemical, automotive, aerospace, biomedical and electronics, even your electric toothbrush has an o-ring that prevents the entry of water to the batteries compartment which would damage the electric circuits.

The appropriate performance of O-rings is a key factor for the operation of static or dynamic systems such as pumps, hydraulic cylinder pistons, engines, compressors, and tanks. Therefore, it is extremely important to test O-rings to set their technical specifications and to evaluate their quality.

Due to the circular shape geometry, the related testing standards of O-rings, like ASTM D1414, include a mathematical expression for tensile elongation that depends on the O-ring and the testing fixture dimensions. This expression can be easily handled with a Virtual Measurement and provides the required flexibility to handle tensile tests of O-rings. Read more

Standards in Paris

In September, several Instron employees participated in the annual ISO standards meetings on the mechanical testing of metals in Paris, France. The technical committee ISO/TC164 oversees several key areas in metals testing – uniaxial testing (e.g. tensile testing to ISO 6892-1/2 and the soon-to-be-released ISO 6892-3/4), as well as ductility testing on sheet metals (e.g. plastic strain ratio & strain hardening exponent), hardness testing, toughness testing (fracture, Charpy pendulum and tear testing), and fatigue testing.

The development of ISO standards covering all of these areas was discussed at length and the voice of all participating countries was heard and considered. Our very own Jean-Pierre Gale, Dan Raynor, and John Cookson participated in discussions covering all areas of mechanical testing, particularly in the progression of the static tensile test standards ISO 6892-1/3/4 and fatigue test standards (e.g. ISO 12108 – Crack Growth, ISO 4965 – Dynamic calibration and a draft of ISO 23788 - Machine Alignment).

There was a strong sense of learning from each other at the meetings and Instron’s involvement reinforces our commitment to maintain our leadership in materials testing technology and our strong relationships within Industrial and Research & Development organizations. We are actively working to drive the standards forward for the benefit of the materials testing community.

Do you have any questions for our Jean-Pierre, Dan, or John? What about comments to share about working to drive the standards forward? Read more

Automated testing of Suture Materials

In our previous featured post Automated Testing: Are You Doing It?, we talked about the benefits of using automation for your material testing needs, such as increased profitability and improved quality thanks to streamlined testing procedures.

In this video, we would like to show a specific example of Automated Testing where the system is configured to perform unattended tensile testing of biomedical suture specimens.



A typical automated test sequence includes the following steps:
- The robot retrieves a batch separator with a barcode label affixed from a rack, scans the barcode, and downloads the specimen and testing information to the Testmaster2 Automation Control Software.
- The separator is then discarded into a bin and a specimen is retrieved from the racks and placed into the tensile frame and tested.
- After the test, the specimen is removed via a specimen removal device at the back of the frame, which utilizes a low-noise, industrial vacuum to aid in full removal of the tested sutures from the grips area.
- The robot then inserts the next specimen to be tested.

Do you think automated testing is a good solution for labs? Leave us a comment to discuss! Read more

Smashing Pumpkins - The Instron Way

Our customers ask us to test all kinds of unusual things and with Halloween approaching, our Apps Lab Team thought it would be fun to test the strength of various fall vegetables: a small pumpkin, a large pumpkin, and a dumpling squash. The video below is of the little pumpkin. Seeing it's size, we were surprised at how strong (and full of seeds) this little pumpkin was. It made us think, "How strong are the kids that smash pumpkins on the road?!"

Do you have something you'd like to see us test? Let us know - we're up for the challenge!

Stayed tuned to our blog to catch the other 2 videos coming soon! Read more

Biomaterials Conference Brings Us Back to Our Roots

The 24th European Conference on Biomaterials, in Dublin, Ireland did not only prove to be a beneficial conference to our Biomedical Applications team, but it turned out to be a winning experience for a student from Imperial College London, UK.

We find it important and necessary to take the time to speak with our customers to understand their needs for biomaterials testing.

Taking the opportunity to meet with the 900+ attendees at the conference, we asked our booth visitors to fill out a survey based on their research, mechanical testing, and impression of Instron. The results help us to better understand some of the recent market trends and plan for the future.

Esther Valliant was the lucky winner of an Amazon Kindle after taking part in our survey on the Instron stand.

The conference provided an excellent forum for scientists and researchers to exchange information and ideas on a variety of subjects within biomaterials and tissue engineering. We found significant interest in mechanical testing and discussed a host of differing testing challenges and potential solutions.

Simply follow this blog to find out where we’ll be next so you have a chance to stop by our booth and talk with us about enhancements you see as beneficial to your daily applications ... oh, and you may win a prize too! Read more

Automated Testing: Are You Doing It?

In an effort to become more competitive, increase profitability and improve quality, and meet or exceed a customer's schedule, companies are turning to automated processes that increase production throughput and profitability, while improving quality and work consistency. Despite the significant initial costs associated with the integration of new technologies into existing operation and the modernization of facilities, the long-term benefits include increased profits, shortened lead times, greater consistency and repeatability, improved quality and customer satisfaction.


Materials testing labs across all industries, including metals, plastics, elastomers, biomedical, paper, and more, have the opportunity to automate many of their R&D and QC testing processes to provide increased throughput and better financial performance of the business. There is a need for testing lab managers to reduce overall operating costs, yet still meet the demands of higher testing volumes, timeliness of results, improved reliability and reproducibility of data and ensured operator safety.

Automated materials testing sytems are a viable solution that satifies all of these requirements.

To justify the purchase of these quite expensive systems, one must have a good understanding of the true value that can be obtained from this equipment, especially in today's economy.

If the economy continues to spiral downward, companies (in all industries) will begin to focus their efforts on running leaner to remain competitive and maximize profits. Running leaner does not necessarily mean reducing head count or minimizing production. Companies are investing resources into systems, such as automated specimen handling systems, when the benefits outweighs the cost.

What are you experiencing in your lab? Read more

eBook Alert: Want a free copy?

We recently compiled a 100+ page eBook on materials testing tips, common questions, and interesting customer stories. And we’d like to share this with you! We would also like to send you a free t-shirt ... Read more to see how you can win one!

Offered to new subscribers of our materials testing newsletter, TechNotes, this eBook is developed from the brains and experience of our application experts.

As we embark on our 50th Edition of TechNotes in October, this eBook compiles the most interesting, helpful, and popular articles from the past five years.

Do you know about the importance of alignment when tensile testing? Have you ever wondered about the strength it takes to tear apart a phone book? Are you aware of the differences between ASTM and ISO standards? What about Accuracy and Resolution?

Subscribe to TechNotes and download your free eBook to find out!

Not only will you find the answers to these questions, but you'll stay "in the know" of what's happening in the world of materials testing.

Additionally, we're looking for feedback ... Did you find the eBook useful? What should we include in the next issue? Would you like to submit an application your working on for inclusion? Leave a comment and we'll send you an Instron t-shirt! Read more

Impact on Composites

A compression after impact (CAI) test is used to measure the residual strength of composite laminates after being damaged by an impact. Such damage can be caused by dropping tools on a laminate or by flying debris. Even if the impact does not result in visible damage, the compressive strength of the composite can be compromised.

The CAI test method and the associated test fixture are outlined in Boeing® Specification BSS 7260. This post-impact compression test is targeted for carbon and aramid fiber reinforced plastic (CFRP) composite laminates. It is widely used to assess the relative performance of composite laminates with different fiber matrix combinations.

As a side note: we were asked to test the compressive strength of the composite, so we simulated impact damage by applying a specific energy with an instrumented impact tester; alternatively, you could use the manual drop weight approach. Next, we used a floor model electromechanical universal tester equipped with our Boeing CAI Test Fixture and materials testing software to apply the compressive force. With customer feedback in mind, we designed the post-impact test fixture with adjustable side plates to accommodate for both variations in thickness and overall dimension.

Read more on our composites testing solutions!

Join us at Composites Europe, September 27-29 .....you can find us at booth 4/F61. Read more

Importance of Accurate Alignment

Your testing system represents a major capital investment for your organization. You make sure it is regularly calibrated for load, strain, and displacement, and that it is regularly serviced. But when did you last make sure that the alignment was correct?

Misalignment takes two forms: concentricity misalignment, in which the centerline of the upper grip or fixture is offset from the centerline of the lower grip or fixture; and angularity misalignment, in which the two centerlines are at different angles to each other. Both impose unwanted bending stresses into a test piece under load and can therefore affect the behavior of the material.

Load frame alignment can change for a number of reasons, including:
- Changing grips
- Installing new or replacement load string components (load cells, adapters, and fixtures)
- Repositioning the fixed crosshead
- Wear or damage to load string or load frame components

The importance of accurate alignment is recognized more and more by accreditation bodies, aerospace corporations, and others. You must be able to demonstrate that your systems meet the alignment requirements specified in many ASTM standards that reference tolerances for either bending stresses or alignment.

ASTM has produced ASTM E1012, which outlines the requirements and calculations for assessing load frame alignment. This standard is frequently quoted as an acceptable method for checking and quantifying materials testing machine alignment.

So, consider requesting an alignment check during your next service visit. You never know when you may need to show that your system is ready for everything. Read more

Standby Modes on Testing Systems?

Q. In these days of increased awareness of the environment, why does Instron still use “standby” modes on your systems?

A. Strain gauge load cells convert the load acting on them into electrical signals. The gauges themselves are bonded onto a structural member that flexes when weight is applied. Temperature effects on the modulus of elasticity of the flexure materials are compensated, using carefully trimmed temperature-sensitive resistors. But it is still necessary when starting a system from a full shutdown state to allow a 15 - 20 minute “warm-up” period that allows the load cell temperature to stabilize and ensures consistent measurements. Standby mode is provided to permit the automatic shutdown of the energy-consuming components of a testing system after a period of inactivity, but it retains the power supply to the load cell to ensure that it remains temperature stable.

Do you have a question that you'd like to see featured in our newsletter and on our blog? Leave us a note below! Read more

Importance of Testing in an Ever-Changing World

For many years, tin and lead solder has been the accepted material for securing electrical components and wiring to circuit boards. Recently, environmental concerns have led to legislation in many countries to outlaw the use of lead and other hazardous materials in consumer goods and other industries.

In Europe, the Restriction of Hazardous Substances Directive (RoHS) has either banned or restricted the use of lead along with five other elements or compounds. This has forced the development of lead-free alternatives to tin/lead solder. Furthermore, the rapid rate of miniaturization of consumer goods has driven the development of novel production techniques. These changes have opened the door to a wave of research and testing for the new materials and techniques.

Solder, along with its higher temperature counterpart, brazing, has been in use for thousands of years as a medium for forming a robust joint between metals. Solder has a lower melting temperature than the metals to be joined. Simply put, the melted solder flows between and around the items to be joined, then hardens to form a conductive bond between them. It is similar to a hot glue bond, but more complex in that the solder material forms a molecular bond with the materials of the pieces to be joined.

A major advantage of tin/lead solder in the proportions of 63% tin and 37% lead is that it is a eutectic alloy; that is, the melting and solidifying point of both materials in the alloy are identical. In non-eutectic alloys, one of the materials will solidify at a different temperature to the other. Between these two temperatures exists a range where the alloy appears solid, but is soft, and movement between the surfaces to be joined is still possible. This movement can seriously weaken the final joint.

There are, of course, disadvantages to tin/lead solder. Its low melting temperature of around 183°C (361°F) makes it unsuitable for use at anything much above ambient temperatures. It cannot be used where load bearing is required. Most importantly, lead is recognized now as a hazardous material, particularly for young children.

On July 1, 2006 in Europe, the RoHS came into effect to require many new printed circuit boards (PCBs) to be free of lead. This legislation, along with similar pressures in other regions, has led to the development and testing of many new solder alloys using tin, copper, silver, gold, and bismuth in different combinations and proportions. Many questions remain regarding the chemical and mechanical characteristics of the new lead-free alloys.

The ongoing miniaturization of electronic components has also driven the development of many new techniques for soldering components to PCBs. An example is the Flip Chip or Controlled Collapse Chip Connection known as C4. In this technique, the integrated circuit has a grid of metal pads rather than wire terminals. Blobs of solder are deposited onto the metal pads. The chip is turned over and placed into its location on the PCB with matching metal pads and the solder balls are re-melted and solidified to form the bond between the pads.

These modern production techniques also require extensive testing to ensure that the resulting products meet their requirements for performance and reliability. Therefore, a worldwide research effort has been underway for years to characterize lead-free solder alloys and to mechanically test the strength of the bonds formed using the alloys and the new production techniques.

Because of the large variance in materials and construction – the different solder alloys, surface finishes, substrates, process conditions, and geometries – no industrial standards currently exist. However, there are several typical mechanical tests that manufacturers and researchers carry out on the bonds between the solder balls and the metal chip pads, such as low and high speed shear tests, cold and hot pull tests, impact tests, and fatigue tests. These tests are useful for obtaining comparative data, but some of them, particularly the pull tests, do not reproduce real-world conditions very well. The need to grip the solder ball either deforms the ball or requires the insertion of a pin by re-melting the solder ball.

High-speed shear, impact, and fatigue testing of solder balls come much closer to reproducing the same failure modes seen in manufacture and end use. They offer a measure of the overall resilience to mechanical shock. An impact pendulum tester using precision high-speed sensors measures the force and position of the impact tool enabling accurate force v. displacement graphs of the test.

Brittle fracture is a typical failure in the intermetallic layer between the solder ball and the PCB metal pad, and pad crater, a fracture on the PCB that leaves a "crater" on the surface. These failure modes are common causes of weak and unreliable joints.

The pendulum tester can also provide useful fatigue data with repeated low-load or high-rate impacts or both on the solder ball. These tests can simulate many fatigue loading conditions with the advantage that the load, energy, and strain can be selected and recorded for every load cycle.

If the product is not performing to requirements, these tests may help determine if design or process changes are likely to result in an improvement. Conversely, if the product is performing to requirements, continued testing can provide a fast, cost-effective, and real-time assessment of product quality.

The accelerating rate of innovation in consumer goods such as computers, cell phones, and touch pads is astonishing with smaller and increasingly capable products being released to the market almost weekly. This demand, along with increasing national requirements for safety and environmental awareness, drives continuous improvements in design, development, and production. In this rapidly changing and competitive environment, the role of testing has never been more important.

Share with us what you're testing ... Read more

We're Talking Artificial Hips in Zurich

Did you know that the first artificial hip was implanted into a human body in the 1940’s, but that the development of total hip replacement did not become customary until the 1960’s? Today, total hip arthroplasty is one of the most widespread orthopaedic surgical procedures carried out around the world, although knee, spine, ankle, and even elbow replacement are also common.

Total joint replacement is normally undertaken to overcome musculoskeletal disorders, such as arthritis, or to replace damaged bone caused by trauma or injury. The main purpose for joint replacement is to restore normal load bearing function with the goal of alleviating current pain and much of the recent innovation has been around material developments and performance improvements.

Mechanical Testing assists researchers during all stages of the product life cycle and is a common practice in many laboratories and research institutes. Research during the design, development and engineering phases of device development utilizes mechanical testing to help understand its behavior and performance. Testing in a production environment helps to verify device quality. Implants must be proved in a laboratory environment for performance and quality, as well as for the device to be regulatory approved for implantation within the body.

For more information on orthopaedic testing, visit our booth (#608) at Orthotec Europe in Zurich on September 28-29th.

View our dedicated page on orthopaedic testing, standards & applications, and more!

Stay tuned for future posts on hip & knee replacements, spinal devices, and osteosynthesis & trauma devices.

Have a question for one of our experts? Leave us a comment below or let us know if we'll be seeing you in Zurich! Read more

Strong and Secure: A Skycraper's Story

Developing a monument to stand the test of time is the thought behind the structure that will soon be 1 World Trade Center.... Recently aired on PBS, the Port Authority of NY & NJ is managing the World Trade Center project. Constructed with a core of concrete, instead of steel and sheet rock, the materials of this super concrete are tested and found to withstand 14,000 psi. And if you need a point of reference, the Hoover Dam can withstand around 7500 psi.

Watch this short video of the construction of this skyscraper and to hear more from the masterminds behind this vision.
*You will need access to iTunes to view the video Read more

Combing Through Resistance ....

When you think of using an Instron for your testing application, what comes to mind? Breaking things, maybe... But testing hair care products? Probably not. Anyone interested in hair care knows how important hair products are to sustain sleekness, strength, and shine. And Good Housekeeping knows what it takes to test the friction of combing hair ... An Instron! Read the full article in Good Housekeeping ....

What testing applications are you performing on your Instron? Read more

The Need for Accredited Calibration

Our customers expect confidence, integrity of data, and reliable test results. Regular calibration of mechanical testing machines to internationally recognized standards by an accredited organization helps provide this reassurance and are vital contributors in reducing business risk and cost.

How often should a system be calibrated?
In many cases, the frequency of calibration is dictated by the requirements provided in standards or procedures specified by the company’s quality assurance requirements. The most frequently used materials testing standards recommend that a system is calibrated annually. Best practice also dictates that the equipment should be calibrated if it has undergone significant repair, configuration, or has moved locations.

What’s the difference between accredited and unaccredited calibration?
An accredited calibration laboratory is subject to an independent, third party evaluation of its competence to perform calibration procedures meeting ISO 17025, the international standard for requirements and competence of calibration and testing laboratories. This includes verification that the laboratory provides measurement results traceable to recognized National Measurement Institutes (NMIs), such as:
- National Institute of Standards and Technology (NIST) in US
- National Physical Laboratory (NPL) in the UK
- Physikalisch-Technische Bundesanstalt (PTB) in Germany

Using an accredited calibration laboratory provides confidence that the calibration certificates will be recognized and accepted worldwide.

Which standard should I calibrate to?
This depends on the testing procedure or quality control requirements. Many testing procedures and standards require that the testing machine has to be calibrated to a particular calibration standard. For tensile testing, the most commonly specified calibration standards are ASTM E4 or ISO 7500-1. Additionally, where strain measurement devices are used, ASTM E83 or ISO 9513 are often specified. Read more

Recent Quake Activities

Did you just experience the East Coast or Colorado earthquakes? For those of us in the Northeast, this isn't something we're used to experiencing. However, out in California, it tends to be an occurrence that most likely doesn't bring as much Facebook activity as today's quakes.

Eighty percent of all earthquakes occur along the edge of the Pacific Coast. Depending on its force, some buildings, roadways or bridges could collapse.

With a daily volume of nearly 300,000 vehicles, one of the busiest bridges in the USA is the 71 year old west-coast San Francisco-Oakland Bay Bridge (SFOBB). This 4.5 mile (7.2 km) long bridge consists of two major spans. Once deemed impossible to build, Caltrans designated the SFOBB as the emergency lifeline route to use in disaster response activities. This requires the bridge to be secure, fully functional, and earthquake-resistant. In 1989, the bridge closed for more than a month due to repairs needed after the Loma Prieta earthquake. In response, the eastern span between Oakland and Yerba Buena Island is now being replaced by an entirely new crossing – making the bridge less susceptible to damage during an earthquake. This is known as the East Span Seismic Safety Project.

"We are using Instron's testing system to tensile test large diameter steel bars (#14 and #18) to ASTM A 615, ASTM A 706 and ASTM A 722 specifications," said Rosme Aguilar, the Structural Materials Testing Lab Branch Chief. "This custom built 2 million pound (8,896 kN) capacity system has replaced our existing testing system because its 1 million pound (4,448 kN) capacity could no longer handle materials of larger diameter and strength that require a higher capacity."

The system, which stands more than 26 feet (8 meters) high, is located at the Structural Materials Testing Lab in Sacramento, CA. As California's only state transportation testing lab accredited by the American Association for Laboratory Accreditation (A2LA), it quickly responded to a recent bridge collapse due to a tanker truck explosion. The lab had the responsibilities of assisting with the damage assessment to determine if the material properties of the steel girders and bent caps had been compromised due to the heat from the tanker truck fire. Remarkably, the damaged bridge was fully functional in 18 days. Read more

Stent Testing

Each year more than a million people in the United States have coronary angioplasty. A stent placed in an artery as part of the angioplasty restores blood flow through narrowed or blocked arteries. Stents - a small mesh tube - help prevent the arteries from becoming narrowed or blocked again and are usually made of metal mesh, but sometimes they're made of fabric. Fabric stents, also called stent grafts, are used in larger arteries.



In partnership with Machine Solutions Inc. (MSI), we provided a solution to test stents during expansion and compression. A typical test can be observed in the video that features a single column system and the RX fixture with MSI’s proprietary segmental compression mechanism. You'll see that the data acquisition during the test is handled by materials testing software that provides radial hoop strength and radial stiffness results.

We know it's important to develop systems that are in accordance with not only ASTM standards, but also international testing recommendations. Here's a few we kept in mind for stents testing:
• The FDA guidance document titled “Non-Clinical Tests and Recommended Labeling for Intravascular Stents and Associated Delivery Systems”
• ISO Standard 25539-1:2003(E) Titled “Cardiovascular implants – Endovascular devices”
• ISO/TS 15539:2000(E) Titled “Cardiovascular implants – endovascularprostheses” Read more

If We Can't Test It ....

We often get asked to help our customers with specific tests that they are struggling to do with their existing test facilities. Where we are not able to offer equipment to meet their needs, we have many customers around the world that offer services for contract testing or research. Find out more on a sample of these customers.

BDC Laboratories provides custom test fixture design, as well as both GLP and non-GLP testing services to the medical device industry encompassing both bench and durability studies. In addition to these comprehensive testing and R&D support solutions, BDC offers silicone mock vessels for device evaluations. Stents and stent grafts, heart valves, and catheters are a small subset of BDCs expertise in implantable technologies.

Confirmed LLC provides medical device testing and characterization services, including corrosion testing per ASTM F2129, Nitinol device transformation temperature testing per ASTM F2082, tensile testing per ASTM F2516, fatigue testing/FEA services, and custom device-specific test development. Confirmed LLC has significant expertise in the development, manufacturing and testing of Nitinol-based medical devices, as well as broader expertise with 300-series stainless steel, MP35N, L605, other Co-Cr alloys, Ti, and Ti-based alloys. Their mission is to not just give you data, but to provide the technical expertise you need to achieve your development goals.

CRITT MTDS, (Centre Régional d’Innovation et de Transfert de Technologie - Matériaux Dépôts et Traitements de Surface), based in Charleville Mézières & Nogent, France, are providers of medical device testing and characterization services COFRAC-Accredited Laboratory for work area n°136 on Orthopaedic Implants. Their capability in material characterization has been developed to various standards for Stainless Materials, Ti, CO-CR according to various standards like ISO 5832; for ceramics, for Polymers, PEEK and for porous coatings. They also offer tests of medical devices according to various standards such as ISO 7206 and ISO 14242 for hip implants; ISO 14243 and ISO 14879-1 for knee implants; ASTM F2077, ASTM 1798, and ASTM F1717 for spinal devices ASTM F543 on metallic screws; and ISO 14801 on dental implants. Their broad capability covers the development cycle from raw material characterization, process qualification, through to final product validation. Read more